Flat flexible cable is commonly used for connecting electrical devices. Flat flexible cable may provide a structure including multiple conductive pathways and may be easily and reversibly bent and twisted in a narrow and crowded space. Various advantages may be provided by flat flexible cable as compared to other cable types. For example, using rectangular conductors as conductive pathways may allow greater amounts of current to be transferred at equal cross-sectional area in comparison with round conductors. This may allow a weight reduction and a reduction in space required for the cable. These advantages have found particular utility in the electronics and automotive industries. The flat configuration of flat flexible cable also allows this type of cable to be mounted behind coverings with limited design depth. Because of these advantages, flexible flat cable is being used to an increasing degree in automobile manufacture as a replacement for cable consisting of round conductors.
Flat flexible cable may generally be provided as a laminated structure or an extruded structure. As a laminated structure, flat flexible cable may generally include a plurality of parallel conductors laminated between opposed insulating sheets or strips. Laminated electrical flat conductors may generally be provided as individual conductors in spool form. The individual conductors may be arranged into a conductor set during the process of lamination using slotted guides. The conductor set consists of individual conductive pathways. The individual conductive pathways may be individually insulated from each other, i.e., arranged at a spacing relative to each other and have a rectangular cross section. The tops of the conductive pathways may be electrically insulated, for example by an insulating sheet, which is laminated onto the conductive pathways. Similarly, a bottom insulator may also be laminated onto the bottom of the conductive pathways. The top insulator and bottom insulator may be laminated together in the regions between adjacent conductive pathways and on the edges outside of the conductive pathways.
Extruded flat flexible cable may be formed by conductive pathways in an insulating sheath by an extrusion process with an electrically insulating plastic sheath. The plurality of conductors may pass through an extrusion die, such as a wire coating, cross-head extrusion die with the conductors maintained in a desired spaced-apart and parallel arrangement. The resultant flat flexible cable may, therefore, include a plurality of conductive pathways that are electrically isolated, but encased in a unitary sheathing. The shape and properties of the finished extruded flat flexible cable may correspond at least essentially to the shape and properties of a laminated flat flexible cable and the sheathing material.